Ok, just to complete the picture, went back to the car after 15 minutes (spent joining and posting previous post) and guess what,started first time, first crank of the engine!! Anybody been here before?... Thanks!!

Hi, today's update: despite starting fine late last night (then took it for a brief spin, around 1 mile), wouldn't start again this morning, same problem. engine seems to fire fine right from the off but won't run for more than a second, then this deteriorates the more you try to start it (I presume this is because of unburnt fuel upsetting the balances). Leave it an hour - same again, fires fine, but doesn't catch/run more than a second or so. It doesn't seem particularly lumpy for that second or so, so its like the engine management decides to stop the engine for some reason - faulty sensor? Would be running on 3 cylinders? - would this be expected to store a fault code?

Anyway, have the car booked in for Friday if I can get it there, will post the outcome...

Ok, not the last update I'm sure, car has been into my local garage but things have changed there and not a very satisfactory outcome, the guy said there was petrol in the engine which I disputed but he was adamant, so he recovered the car and drained the tank etc, meanwhile I tracked down out all my fuel payments from bank statements and found associated receipts - diesel all the way. Also checked the fuel station I also use - no fuel issues. But the car was at least starting, albeit reluctantly (but that cuold have been the battery from so many previous attempts). Anyway, drove it away, started it this (cold) morning - perfect first time start, runs as well as its ever done. So car is running for the moment (which is good) but can't believe any closer to a resolution (though I guess changing the fuel filter as part of the drain etc may have helped somewhat, thus can cause fuel pressure issues). However, done some more research and I'm now thinking its an EGR valve issue, for the following reasons:

- EGR valve sticks open - can cause exactly the same 'it fires but does not catch' symptom

- slightly reluctant to pull in first when cold (not lumpy/missing, just a slight feeling of 'holding back')

Does anybody concur with this?

I've read that you can disconnect the EGR safely as a test, I'm thinking I'd like to try that next time it doesn't start, if it does then start with the EGR valve disconnected thats pretty conclusive isn't it?

Can anyone guide me through how to disconnect it? Is it just a clip, or does it involve unscrewing stuff? Anything to be wary of in doing this?

Ok, said I'd post the outcome so here goes. The car ran ok for a couple of weeks over Xmas then steadfastly refused to start one morning. Only had one chance for free recovery so it had to go to Ford. They diagnosed as EGR valve stuck open. £480 lighter having had the valve (which is integral with inlet manifold on the S-max) replaced, so far so good. Hopefully that's that for another 80,000 miles.